1. Field of the Invention
The present invention relates to a pressure-measuring glow plug for use in a cylinder head of an internal combustion engine according to the definition of the species in Claim 1.
2. Description of the Related Art
A pressure-measuring glow plug is known from published European patent application document EP 1 637806 A2, having a glow module and an electronic module, the glow module including the components of a glow plug and the electronic module including a sensor unit having a pressure sensor and a plug housing for contacting a connecting plug. The glow module is surrounded by a massive glow plug housing, which is connected to an electronic module housing. The electronic module housing encloses the sensor unit and partially the plug housing. The sensor unit and the plug housing are two separate components, separated from each other.
From published Japanese patent application document JP 2009 22 90 39 A1, a pressure-measuring glow plug is known having a glow plug housing, in addition, a signal processing unit for preprocessing the signals of a sensor unit being integrated into the pressure-measuring glow plug. In this context, the glow plug housing accommodates a heating pin, the sensor unit and the signal processing unit. On the glow plug housing, on the combustion chamber side, an additional protective housing is mounted, which is fastened via a diaphragm and connected to the glow plug body. The electrical plug connection adjoins the glow plug housing on the connecting side.